1. Field of the Invention
The present invention relates to a chemical vapor deposition apparatus and a method of forming a semiconductor epitaxial thin film using the same, and more particularly, to a chemical vapor deposition apparatus, which can grow thin films on both surfaces of a substrate using a metal organic compound, and a method of forming a semiconductor epitaxial thin film using the chemical vapor deposition apparatus.
2. Description of the Related Art
The demand for nitride-based (GaAlInN) light emitting devices (LEDs) is increasing explosively. The nitride-based LEDs are used in portable phone keypads, liquid crystal display (LCD) windows, TV backlight units (BLUs), and illumination apparatuses. To meet this trend, research has been conducted as to introduce a large-diameter sapphire wafer. In other words, the diameter of the sapphire wafer used to grow nitride or semiconductor oxide (e.g., GaN, ZnO, etc.), which is applicable to LEDs, to an epitaxial thin film increases from 4 inches to 6 inches.
A current chemical vapor deposition process can manufacture about 10 sheets of 4-inch sapphire wafers at a time, but it has a disadvantage in that there is a limit to the mass production thereof due to a structure of a susceptor which supports the sapphire wafer.
In addition, a large-diameter wafer has a limit on use due to a degradation of performance, such as a wafer bowing effect or cracking. The wafer bowing effect or cracking may occur due to a high thermal stress, which is caused by a great difference in thermal expansion coefficients between a nitride semiconductor and a sapphire wafer used as a growth substrate, and an inherent stress, which is caused by a difference of a lattice constant during a thin film growth.